Cobalt Neo-Therm or cheaper heater for Spec III?

[drabina]

I need to buy an adjustable heater for Fluval Spec III (2.6 gal) tank. Our LFS has Cobalt Neo-Therm for $43 and it is also waiting for some cheaper heaters which they will get by the end of the week. By cheaper I mean $25 heaters like Hydor Theo. Aquarium hosts one Betta fish and possibly a snail is going to be added in the near future.

Is it worth it to get the Cobalt Neo-Therm or cheaper heater will suffice?

[54seaweed]

both those heaters are a bit rich for a 2.5g tank

I would prob steer more towards something like this
Aquarium Heater: Cobalt Aquatics Mini-Therm Heater
or even something like this
Aquarium Heaters: Tetra Submersible Heaters