The top link is a lot better (and faster)
The bottom link is hard to tell. It looks the same as the cheap venom.
If you can squeeze $20 then the HK 50 watt charger can be had. If you are locked into tower then perhaps that 200 watt $59 scratch and dent charger is the best deal going right now. You will like 200 watts a lot more than 50.
http://www3.towerhobbies.com/cgi-bin...0240&search=Go