Need advice on a limited selection of heatsinks

I'm getting ready to finally upgrade my old pc and I want to get a combo from Monarch since it will be assembled and tested for me. I've tentatively decided on the MSI K8N Neo2 Platinum w/ Athlon 64 3500+ 90nm and 1 GB (2 pcs 512) DDR (400) PC-3200 Corsair XMS (TwinX1024-3200C2PT).

My question is, which of their available heatsink/fans should I use? I don't plan to do any overclocking but I'd like to make sure the system is cool enough that I'm not right on the edge of acceptable temp (whatever that may be). Their choices are:

CoolJag JVC681A $8
http://www.monarchcomputer.com/Merchant2/merchant.mv?Sc...

Dynatron A21 SK-V2 $22
http://www.monarchcomputer.com/Merchant2/merchant.mv?Sc...

Thermaltake A1772 $35
http://www.monarchcomputer.com/Merchant2/merchant.mv?Sc...

Thermaltake A1838 $25
http://www.monarchcomputer.com/Merchant2/merchant.mv?Sc...

Thermaltake AMD K8 Venus 7+ $20
http://www.monarchcomputer.com/Merchant2/merchant.mv?Sc...

Price is a consideration but I don't want to skimp on cooling so if I need the most expensive one, I'll buy it. The reason I didn't include the retail heatsink/fan as an option is the price difference to get the retail chip in the combo is $65 and I assumed it wouldn't be better than the oem with aftermarket hs/f. Please correct me if this is wrong.

One more question - They charge $14.00 to install thermal grease. Should I get it anyway? It's listed as more an optional thing but I always thought you pretty much had to put thermal grease on.

I'd appreciate any advice you could offer me.

PS someone on another board already suggested I get the Zalman cooler from Monarch. They do sell it but I called them and they don't offer it with the combos because it's "too big and bulky for a combo". <P ID="edit"><FONT SIZE=-1><EM>Edited by Clyde on 11/30/04 03:07 AM.</EM></FONT></P>