Having just wrestled with this two weeks ago I will tell you give you my view point. As others have said, it really depends what you are going to use it for. If you are going to be welding or a lot of oily work, metal plate makes a lot of sense. My needs are more assembly related.
I found some bowling alleys about 1.5 hours away on Craigslist and drove up to take a look at them. One thing I learned is that there are nails all through the bowling alley tops. Sawing them was going to be a bear. You may miss nails on a cross cut, but you will hit a ton if you need to do a rip cut. Also, the top was not as flat as I would have expected. I could feel variances that I suspect was because they had been stored in an unconditioned warehouse. I did not want to deal the nails and refinishing the top, so I passed.
I ended up using two layers of baltic birch plywood (7-ply), topped with tempered hardboard (masonite), trimmed out with some maple. I wanted a bit thicker profile, so I
built up the front edge with some scrap baltic birch to give me 2.5" of thickness. This gave me a good clamping edge, instead of an apron. I countersunk the screws for the maple trim and plugged them with walnut plugs.
Somewhere on the web I read to use sanding sealer on the masonite. I did that and it came out very blotchy. I ended up replacing it and just using minwax poly(3 coats), which worked out nice.