I have 2 "mystery" snails (big yellow ones, possibly apple snails) in my tank along with 4 red ramshorn. 3ft tank with 3 axies.
They have all been happily co-existing for 6 months or so now.
No problems with the snails trying to eat the axies. Only problems with the snails constantly laying eggs everywhere.
If you do decide to add a snail to your tank, watch closely. I am in no way recommending the idea. I just know that under the right condidtions (enough room/live plants for snails to eat algae off) snails and axies can live quite happily together.