Hi, I've used Eagle (only) for a couple of years, and recently did a 
575-component, 1400 net 4-layer design.  Eagle can do it, but you start 
to practical limitations.  For example, there is no way to selectively 
hide "ratsnest" airwires, so while routing a section (by hand, the 
autorouter is fairly useless on larger designs) irrelevant airwires 
crisscross the screen.  Just being able to turn of ground(s) (this 
design has 7!) would have been a big help.  An easy feature to 
implement, not needed for smaller designs, so it's not there.

Polygon fill (copper pour) is slow with big boards ... it is the only 
thing slow on my computer (Athlon 3400+, good vid card, 2Gb ram). 
Redraw with copper pour shown is kinda slow.

Drawing copper pour areas becomes awkward when you want the same ones on 
each layer of the board.  Various "keepout" polygons apply only to top 
and bottom, and a hack it required for inner layers, no explanation just 
not readily available.

Eagle UI is rather quirky, there is definitely a learning curve.  ULPs 
(user language programs) aren't documented, there are a bunch, and some 
are vital for bigger designs and professional use.

All this said, I've done at least 30 boards in Eagle, and am quite happy 
with it.  But I may do a 600+ component 6-layer design in the coming 
months, and I'm hesitant to do it in Eagle.  Can it do it?  Yes.  How 
much time will be spent that could be avoided with a $5000+ EDA system? 
  Not sure, but definitely a number of hours.

Anyway, as always it is a time/money tradeoff.

J



Mark E. Skeels wrote:
> (Oops. forgot the tag; it's been a while since I posted here...)
> 
> 
> Hi, folks,
> 
> I've been using PCAD/TangoPCB for years. Recently I had occasion to lay 
> out a PCB on which the component count exceeded 400, and Altium wants 
> $4000.00 US to upgrade to a version that removes the 400 component 
> limitation.
> 
> I can get Eagle Professional with no such restrictions complete for 
> $1200.00 US.
> 
> I know a lot of people use Eagle on this list. Has anyone any experience 
> laying out larger pcbs like this? (At least it's large for me) and if so 
> have you been satisfied?
> 
> I'd be changing horses in mid-stream, so to speak, as I'd have to master 
> the user IDE of Eagle and also redraw the schematic and relay the 
> artwork. I generally like PCAD. However, long term, it might be a better 
> solution all around to switch over to Eagle.
> 
> Please give me your thoughts,
> 
> Mark
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