Hello Northern Neighbor!
The good news is that the concept is great, the bad news is that unless you have real loose soil anyway, the ones I'm thinking you're looking at [Campbell Supply in SF had one that looked identical to the consumer grade ones I seen online] fall short in several areas as a combination machine.
The tines are flimsy and spaced too far apart to get a thick fill without several passes anyway. The commerciall ones have a rather smaller diameter, and tight spacing; a few tine style, but more often like a field disk minaturized [of course this very tight spacing is more for new than overseeding]. Also the drop type spreaders like built on the unit at Campbells aren't noted for very even seeding [not my largerst concern].
On the other hand the tines are too small far much aeration benefit.
I got a "heavy duty" [compared to Menards and Runnnings] lawn tractor spiker from TSC (Rugid, Red Devil, and Precision, are all the same, just regional labels it seems) for $125. Not exactly heavy duty in my mind, but it got into the tight areas I needed it for [I also had to redrill the lift bar, so I go more range from my wheels; they hit when the ground when the tines were pretty shallow {though great for seeding}]. I ran a pass [more in places] with some pretty good weight [perhaps 150lb]; then seeded [you can use a broadcast, or even a drop spreader, or whatever you get the best results from]; then I went over everything crosswise. For setting the seed [not even required if you get a good result during aeration]; I tried some without any weight, but thought about 50 to 100lb was about right; you'll need to play with your own soil and moisture conditions.
Not a perfect solution, but for a "combination" machine I think you'd be happier. If you really need aeration bad, a plugger [or maybe a wide toothed drum aerator] will make the spiker look like a garden rake. /forums/images/graemlins/tongue.gif
Good Luck! /forums/images/graemlins/cool.gif
