Question about brand of heater

[Camden]

Anyone know about Pro Heat Glass Aquarium Heaters? They are submersible and pretty cheap. Any feedback would be helpful. Thanks.
http://www.aquacave.com/detail.aspx?ID=370

[discusdave]

John at Jehmco carries them, and he told me t6hey were getting good results with them. I have about 7 operating in my holding tanks right now and they see to work well.

They remind me very much of Visi-Therms in their construction.
Regards,