Get the bullet rack since it comes with the seat post clamp/adapter (which you will have to buy separately if you buy another brand) and IF the rack fits your bike...ask the seller or e-mail Electra ( sales@electrabike.com or scott@electrabike.com - general q's or josh@electrabike.com - tech q's)...ask about max capacity (lbs) that the rack is rated for.

Electra, http://www.electrabike.com/miva/merc...ct_Code=368424 , lists the same rack for $39.99 ($10.00 less, although out of stock).

Delta racks aren't bad if you don't mind silver instead of chrome:
http://www.deltacycle.com/all.php?cat=4