(ET) name names: battery chargers

[tbamc <tbamc gbta net>]

Now that you've got me straightened out on small chargers for my AA and 
AAA batteries, I want to get something for my larger batteries.   :-)

I'd LIKE to be able to charge car, E-T, and gel batteries, 6 and 12v, 
with a charger that will be smart enough to do each of them 
appropriately.  Don't want it to take forever to charge, but speed isn't 
a priority.

After studying the archives and doing some research I've found some 
fairly expensive chargers that would fit the bill, but very few that are 
less than the $100 limit I'd LIKE to have.

One that seems like a good fit--though 6A is max current--is this:
http://store.schumachermart.com/sc-600a.html.
It says it will do AGM's but doesn't mention gel's.  (It's larger 
version the SC 1000A--which won't do 6v--has a selector button labeled 
AGM/gell, so I'm guessing choosing that mode works for either one, and 
would be the same on the 600A?)
Schumacher tells me it uses 3 stage charging--current, V, then float.  
And, it's less than $50.

IIRC, some had concerns about inadequate max current.  I do have a 
couple old chargers with 10A capability, if that helps.

Appreciate any thoughts you have about this one, or others I might have 
missed.

Thanks.
Thon

On a related note:  WHY are so many chargers so expensive??  Are the 
parts themselves that expensive?  I would have thought with modern 
electronics  and technology this would be fairly cheap to do??