There are a number of great posts on the MSR Lightning Ascents on this site, I suggest searching that topic.
Lightning Ascents won't give you quite as much "flotation" as the classic aluminum tube frame style snowshoes, but Ascents will save your ass in frozen hard pack every time when going up, down or side-hilliing.
I use Ascents and you are v close to my size, I run 25" w/o a pack or a light pack. In v soft powder or w/a heavy pack you'll want the 30"ers for sure. Extended tails are an imperfect solution but work.
Adding tail extensions on the 25" models will give you more float, but will shift the center of your balance to front of the snowshoe because the foot hinge point is designed for that 25" format not 30". This is okay when climbing, but a bit of a PITA when descending in soft snow, not a huge PITA, but enough of a pita. I found 'cause the snow under evergreens can be v soft and the front of your snowshoe will want to submarine and dive down a little while your extended tails will tend to float more.
Anyhow, great shoe. You cannot go wrong. And they hold their resale value pretty well.
My 2 cents, buy the 30" if you intend to carry a full pack with winter gear. Buy the 25"ers if you will mostly be day hiking or training. Drop me a note w/any questions.
Depending on where you live, you might find someone that would loan you a set for a weekend to try out. You could always post and ask...
Count on the fact that it may be VERY difficult to find Lightning Ascents this year, so buy them EARLY. Last year had many folks out and about due to COVID and snowshoes were tough to find. This winter could be a repeat.
Best,
JL