SATA drive speed question

I'm looking for a 2.5inch SATA harddrive, my question is which is fastest out of the following?
-5400rpm with SATA-300 interface
-7200rpm with SATA-150 interface

If I had to compromise which one will offer the best performance?

7200rpm>5400 rpm

the sata interface speed is not a factor in speed, since laptop hard drives cannot even pass the 70-80MB/s barrier, even ATA 100 would be fast enough.

Of course, 7200rpm also draws more power/kills your batteries faster and produces more heat. they also tend to be more costly and smaller.

I own one, and i am not that happy with it. i would have rather a 160 gb 5400rpm hdd than my current 100gb 7200rpm hdd - its just too loud, hot and drains too much power. plus, performance isnt too much of an issue in laptops if one just does word/internet. laptosp are not meant for gaming either and usually dont have insanely powerful components. however, i am pretty sure that a 320gb 5400rpm hdd will perform on par with a 100gb 7200rpm hdd, due to the nearly 3 times higher data density, it doesnt need to spin as fast to read just as much data in the same time period. what the 7200rpm hdd will excel in though will be access time.

but of course, if you want absolute performance and have money to burn, 32gb MTRON SSDs are the fastest hard drives you'll find. RPM-less, since they are solid state. very little power consumption, no noise, little heat, high price, and high performance. oh, low capacity too.

I'm planning on using the drive on a desktop PC in an external drive enclosure using an eSATA interface. Thank you for the advise, I think I'll go for 5400 drive if you think noise will be an issue as well as power. My main reasoning for a 2.5 inch drive is down to space and the fact that it can take the power from USB where as 3.5inch would need external power (haven't be able to find 3.5inch which can use USB power so I assume its not powerful enough for that).

thats another thing with 7200rpm hard drives. i have put one in an enclosure and due to higher powere requirements, it required a power adapter which was not included with my case, since they expect people to use 5400rpm hdds. they did include a power jack for those who want a 7200rpm though - which i did end up using, until i sold off the case to somebody and use the hard drive somewhere else.

Thank you so much for your replys, I think thats made my mind up, 5400 it is.