[blykins]

If you can install a clutch with a regular fork and throw out bearing, by all means do.

Some of the downsides:

1. Price. A clutch fork and throw out bearing would be about $100. A hydraulic throw out bearing is at least $300.
2. If it leaks, it will leak all over your clutch disc and ruin it.
3. If it leaks, plan on pulling the transmission....which can be a pain in the butt with some Cobras.

The only upside I know of is that they're good if you have limited space.

I would heavily advise against it though.