Yamaha DTXpress/DTXplorer/DTXtreme

Hi my name is Dennis and I've played drums for more years than I care 
to remember...  I've always played acoustic drums and hadn't
really 
thought much about electrics...  I'm not an acoustic drum snob, 
electrics just weren't something that interested me until a
recent 
shopping trip to Sam Ash for drum heads.  While I was drooling over a 
Tama Starclassic set my daughter wandered into the booth where they 
keep the electrics and sat down and started to play them…  Well
after 
a period of lustfull gazing at a few of the nicer acoustic kits I 
picked out the heads I needed and beckoned to my daughter...  She 
said Dad before you leave you've got to try these...  Well to
make a 
long story short (too late, I know) I sat down and was immediately 
impressed...  I loved the sound and the feel…  I had no idea how
far 
electric drums had come since the days of the old Simmons drums (late 
70's early 80's to my recollection). That was my last
experience with 
electrics and I didn't like them…  Now I've decided to
take the 
plunge…  I'm going to buy myself a set of electric drums…
 Due to 
financial concerns I have been looking at the used Roland V-Clubs and 
the Yamaha DTXpress series sets on ebay…  I'm leaning towards 
Yamaha…  They seem to have more features ie: groove check
etc… There 
also seems to be a pretty significant price spread between the 
original DTXpress kits and the DTXpress II or III kits…  I'm
looking 
for some advise from a few seasoned veterans of the DTXpress
series…  
The drums I will be purchasing will be used for home entertainment 
about 99% of the time…  There is no worry about road worthiness
etc…  
What are the big differences between the original and the series II & 
III sets…  Is it something that a first time electric drum set
owner 
will find a big deal…  I'm thinking that my home use for 
entertainment purposes only would be satisfied by a good solid used 
set of the DTXpress originals…  I also have this nagging feeling
that 
I could be wrong…  Any advice, insight, input etc… would be
greatly 
appreciated…

Dennis