#1
I have found a hybrid amp that has one tube and the rest is transistor based, any good?
#2
There is no way of knowing unless someone has experience with them. In general a full tube amp is preferable to a hybrid. Hybrid doesn't mean any particular amp design. An amp could be mostly tube with some op amp amplification and it's a hybrid. An amp could be almost all solid state with just one tube for tone shaping and it's a hybrid. An amp could have an all tube preamp with a SS power amp, or the opposite an all tube power amp with SS or digital preamp amp, and it's a hybrid.

They are all different and it's up to you to test them to find out if they're good enough.
#3
Depends. Most of the time the tube doesnt seem to do much to help the amp play much better. Ive had a behringer hybrid that didnt sound very tube like at all (it is a behringer). But for example with the vypyr tube compared to the solid state version its quite an upgrade.
#6
I'm going to close 2 of the 4 threads you have open on the same subject. Try to keep your discussions to one thread, please.