I've never once in my life messed with a bow thruster, but what I HEAR is that unless you get a model with a little door that shuts off the sides of the tube, they induce a lot of turbulence at the bow and adversely affect sailing performance. Again, this is totally hearsay.
Over and over again I read in the cruising rags to go simple. Do you really NEED a bow thruster if you're going to be anchoring out a lot? A seriously sized anchor and good rode, and then a backup anchor and rode....and then a nice dinghy with a decent sized outboard motor would seem to me to be a better place to spend the $$$.
Just my humble opinion, from someone who's done no cruising at all.
1968 Selmer Series 9 B-flat and A clarinets
1962 Buesher "Aristocrat" tenor saxophone
Piper One Design 24, Hull #35; "Alpha"