Isinglass opinions?

My lhbs guy started threat I use isinglass on my next batch, in secondary, for clarity. The batch in question is a cream ale, and I will be bottling in clear glass. The ship proprietor is extremely well respected in the local beer scene (has taught a few college level brewing courses,i hear), but I have two questions to ask you all:
1, what are your experiences with isinglass.... Will it make a noticeable difference?
2, should I go to secondary at all? I've seen mixed that's on 2ndary here, but the lbhs guy said to do it. I plan on starting in primary for no less than 3 weeks, bottle conditioning for another 3 weeks, then drinking it in 4 hours with friends at a spring bbq...at which time we will discuss the Eagles upcoming systematic self destruction (while still dominating the nfc east)

Thanks.

I've brewed for over a year, and am by no means any expert, but I have never used a clearing agent and my beers are very clear. I have only used a secondary fermentor once and did not think it improved anything. Again these are only my opinions, but I like to keep things simple.

NRS