There are big differences in reception range and features in WAPs. Since this is a networking question, that's where the question should be asked.
Briefly: Back when 11g first came out (years ago) MacWorld mag did a range test of both WAPs and ibook vs Ti PB. The AEBS did not have as good a range as the best 3rd party WAPs with their external antennas, but it was as good as the middle-of-the-road 3rd party WAPs (to the best of recollection, keeping in mind that's it's been years.) The external antennas make all the difference, mostly.
Some time ago, PCWorld mag did a review of WAPs, and at that point the Buffalo Airstation came out on top, afai remember. This in spite of having an internal antenna--must just be better antenna design. Hawking is also a good brand. I've got both, and I'd recommend either. Check the mags to see if there's any more recent reviews.
OTOH, if you're not looking to cover a large area, just buy whatever's on sale or rebate. But, getting something good from the beginning is the best way to go.