rpcminer-cuda is slower than default OpenCL miner in guiminer

[superarthur]

I've been using the default OpenCL miner in guiminer, and it went up to 26-27 Mhash/s
I've now read about rpcminer-cuda and I am using that instead, but it only gets to 24.6Mhas/s
Though I temperatures are lower using rpcminer-cuda compared to the default OpenCL miner
Is this usual? Should I keep on using rpcminer-cuda? Or switch back to the default miner?

[Gator-hex]

Don't use nvidia graphics cards full stop you'll waste more money in electricity that you mine.

https://en.bitcoin.it/wiki/Mining_hardware_comparison

[superarthur]

Don't use nvidia graphics cards full stop you'll waste more money in electricity that you mine.

https://en.bitcoin.it/wiki/Mining_hardware_comparison

I am considering getting a new PC for mining, but I am not sure if it will still be a good investment. (Since now everyone is doing it, the mining would be more competitive and harder.)
It's also a pain trying to get a decent PC in the UK. I don't trust online companies enough to buy a PC and have it delivered. And I simply can't find decent enough PCs in chain computer shops (e.g. PC world).
If I were to get a new PC with Ati card, I am considering this one: http://www.dinopc.com/shop/pc/-b-NEW-b-Raider-AMD-X6-6300-94p1640.htm

For now, I can't just change the graphics card in my laptop. My bills are included in the rent, and my laptop keeps the room warm in this cold weather. LOL