One type of tires discussed here at the forum was the Michelin "Defender" tires. These tires are not advertised directly as LRR tires but only as "Energy Saver" type of tires. They do have a 90k warranty for mileage and cost a lot less than the LRR tires Michelin does sell for the Leaf "Premier A/S" which cost nearly twice that of the "Defender" tires.
I did some research and it seemed that the "Defender" tires would be a compromise between cost and performance for the Leaf. The good news was, I had a family member with a Leaf that just got a brand new set of Michelin "Premier A/S" tires on their Leaf (and payed the premium for them), so I actually had another Leaf that I could compare to mine.
My original tires were the stock Ecopias that came with the Leaf. I would rate their performance over the life of the vehicle as average. They had average grip, average handling, road noise, etc. The one thing I did have a lot of was data for trips. I have one trip that I use to gauge my vehicle performance that is a 26 mile drive through country roads that is fairly level, straight, no stops trip (no turns, stoplights, traffic, etc.) and the same speed the entire way (50 MPH) It is a great way for me to test different tire pressures, climate control settings, etc. and get pretty consistent results using nothing but cruise control the entire way.
As a data example, my Leaf could do this trip on the Ecopias and always score exactly 5.2 efficiency every time with fair weather conditions (not hot or cold or windy day). I would run my Ecopias at 40psi to get this consistent 5.2 score for every trip.
The day I replaced my tires with the brand new Michelin Defender tires, I could tell a difference right away. I could hear the tires stick to the road as I turned corners, drove around town. They were nice tires, don't get me wrong. Great ride, quiet ride. The next day I had a chance to do an efficiency test on my faithful route to see how they stack up against my old Ecopias. The day was one of those great weather days, not too hot or cold or windy. All 4 of my tires had 36 psi cold pressure, so I wanted to see how that "stock" air pressure would do on new tires.
I drove my faithful route and at the end was surprised to only manage 4.0 efficiency for the trip. I have to admit, that did kind of worry me, I was thinking "dang I am going to lose some driving range with these tires." I almost thought about returning the tires if I was going to lose 23% off my driving range, yikes! But, I didn't want to throw away the tire performance from just one test. I figured from what I read online that new tires, more rolling resistance, need to wear them out a little and see how they perform in a later distance test.
In the mean time, the range hit was quite noticeable. The GOM is bad enough for range anxiety, but it was really showed it for these new tires. I figured I needed to do something to try and keep my range up as best as possible until the tires had some more wear. In the following few days, I had another opportunity to take my "fair weather range efficiency test" route again. This time, I inflated the tires to the maximum cold pressure of 44 psi. My same trip this time scored me a 4.5 efficiency by only increasing the tire air pressure to maximum. I figured this would be a good compromise until the tires had some time to wear and I didn't really notice a handling or ride difference running maximum cold pressure either, which was surprising. The vehicle felt just as good at 44 psi as it did at 36 psi, so I was impressed with the tires for that reason alone.
Fast forward to 1,000 miles of new tire usage, my test route would gradually start to score better and better. After about 1,500 miles of new tire usage, I actually hit 5.0 efficiency again on these new tires. With that new goalpost, I started to gradually lower tire pressure to see at what point it started to affect my efficiency. I could take the tires down to 37 psi and still score nearly 4.9 to 5.0 on my range test route after 2,000 miles of new tire usage. My tires have over 4,000 miles now and I run 40 psi in them to give me a good balance of efficiency (I can score 5.2 on my test route just like my Ecopias did) and performance for driving.
I believe that even though the Michelin "Defender" tires are not advertised as replacement LRR tires, they perform very similar because these tires are suppose to last 90k miles, so they must have a stiffer, harder compound construction which gives the same benefit as a LRR but without the added cost.
How do they compare to the actual LRR tire that Michelin sells, the "Premier A/S". Well, I had a chance to test those as well thanks to some Leaf vehicle loaning. The Premier A/S tires can achieve at 36 psi when new that the Defender does at 44 psi when given time to wear. The Premier A/S will still out-perform the Defender when using a direct 36 psi to 36 psi comparison. The only way to even up the score is to raise the Defender cold pressure psi to maximum. If you run the Premier A/S at a higher psi (like 40 psi) then it can score better than the Defender at the same psi. Example, the Premier A/S at 40 psi on my test route can score 5.6 efficiency but my Defender at 40 psi can only hit around 5.2. On the same test route, the Premier A/S at 44 psi (max) can score 5.8 efficiency but my Defender at 44 psi (max) will top out at 5.2 efficiency.
In conclusion, if you want to replace the stock Ecopia tires, either tire of the Michelin Defender or Michelin A/S LRR will beat out the stock tires in the long run. If you want to save money and don't mind running some higher tire pressure, the Michelin Defender is a great budget tire in this case. It will be rough when new, but once worn, they work nice and still give a great ride. If you have some extra money to spend on tires or just want to absolutely maximize your Leaf range, then the Michelin A/S will do this. It still provides a great ride and you don't have to baby the tire pressure as much. Either way, both should out-perform the stock Ecopia tires, so anything other than the stock tires will make you happy.