Ok guys here is the deal with the switchblade since there hasn't been a lot of posts by people with experience with them. I have had 2 Avalanches without it, 1 with; 1 Enzo without it and 1 with it. There are a few pros and cons, though let me preface this by saying I would NEVER give back my switchblade - I would rather give up my tower first, but with that said let me continue.
The main pros to the switchblade is that it allows you to easily adjust the size and shape of the wake. The switchblade pitches it up more than if it was not on - on an avalanche making it similar to a SAN 210 and on an Enzo making more similar to a SAN 220. It works awesome and if used properly can change your boat wake to be exactly what you want it to be (i.e. go from steep to rampy or vice versa). For wakesurfing it is absolutely awesome with one exception that I will say in the cons section. Also, anyone who says that you can't steer the boat with it on has either never driven a boat with one on or they were driving a boat with a switchblade that had not been properly mounted on.
Now the cons: The biggest con with the switchblade is not really in itself but rather the people that use it. I am not surprised by bill's comment on the dealer talking about it, since far too many Centurion dealers dont have any clue how to properly equip the boats they bring in. The switchblade is not a device to just either turn on or turn off, you adjust the degree to which it is engaged depending on how much weight you have in the boat, where it is situated, etc. Basically you just look at the wake and adjust either up or down. Most the time i have the switchblade set at about 3 (out of 7) and it is awesome. The only other downside to the switchblade that I have encountered (and it is the reason that Inland Surfer and a number of other surf guys dont use it) is that for wakesurfing it makes the wave a bit "rougher" at the top. You also have to take into account that these guys have their boats weighted up with about 2500 lbs. of ballast and at that point the switchblade would basically become pointless. I love it for surfing, but then again I am only putting in about 500 lbs. above the standard factory ballast in my Enzo SV230. For the most part the less weight you have in the boat, the more you notice the switchblade and the bigger the difference will be when you use it.