Alternative to Photoshop

I was wondering for a while whether there is a decent alternative to Adobe Photoshop. I mean a serious photographer shooting always in RAW, who doesn't want to loose any of the data captured by the camera - i.e. processing the files in 16-bit until the last save.

Remark: To outline my photo editing needs:

• minimum: Full 16-bit editing, including layers, noise removal plugin, curves/levels, blurring, cloning, color adjustment;
• optional: Support of Canon EOS 40D RAW format;
• important: easy to use interface suitable for intensive workflow

Recent version of Corel Paint Shop Pro Photo X2 looked promising, so I decided to give it a try.

Unfortunately it isn't suitable for people like me. I will list the limitations in the order I experienced them, not in the order of importance:

• PSP X2 can't open RAW files from my Canon EOS 40D - not critical;
  
• PSP X2 can't properly handle TIF files saved with ZIP compression - not critical;
  
• PSP X2 can only save 8-bit and/or flattened files in common formats (TIF, PSD), and can only save multi-layer 16-bit picture in it's own format - not critical;
  
• Most filters/effects only work in 8-bit mode as it was with photoshop several years ago. - not critical, as long as layers, curves, levels and blur work in 16-bit mode;
  
• Some tools only work in 8-bit mode, e.g. clone - this is critical for retouch;
  
• Using on the same PC, PSP X2 works much slower than Photoshop CS2 or CS3 - may be critical, but probably can be addressed by a faster PC with more memory.
  

Overall functionality of PSP X2 is quite impressive; and many (most?) of Photoshop plugins work with PSP. The price of PSP X2 is much more attractive comparing with Photoshop. Also, some workarounds are possible to overcome the above listed issues.

However, considering limitations altogether, and considering intensive workflow my conclusion is that Corel Paint Shop Pro Photo X2 is not a decent replacement of Adobe Photoshop CS+ for serious photographers. Perhaps one of the next versions will make it suitable...

Other alternatives?

• GIMP isn't - not only it is very uncomfortable to use but it still doesn't support 16-bit editing.
• Photoshop Elements 6 isn't an alternative either because of very limited 16-bit support - only a few filters supported in 16-bit; and adjustment layers don't work in 16-bit mode.
• Googling for 16-bit programs I found Picture Window Pro 4.0. Tried that one - yes, it supports full 16-bit editing, but the interface isn't convenient and no layers supported at all.

Conclusion: At the moment there seem to be no other software than Adobe Photoshop CS3 that can suite my needs. It is priced high, but not without a reason. And, despite it's high price there are options available to obtain it cheaper than a standard price (I mean, legally). Checking on eBay I found quite a few offers in a range of 250-350 USD for a full-boxed-retail-version.

GIMP isn't too bad, but lacks 16-bit support and has non-friendly interface
PSP X2 is actually quite good, the only serious missing point is lack 16-bit editing.

Remark: 16-bit editing is very important in case of intensive digital manipulation. Editing in 8-bit will result very quickly a non-continuous color representation. You can easily see that effect as a comb when executing Levels command. This might not be an issue for personal photographs or for minor editing, but this is not acceptable in most professional use.

Remark #2: I've got impression that PSP X2 beats Photoshop Elements 6 if you compare them. Actually PSP X2 is positioned in the same market area as PS Elements and isn't competing with the "real" photoshop. However, adding 16-bit support and keeping it low-price would make it a serious alternative to Photoshop itself rather than just Elements.
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