Upgrading from Kx to K5

I started my walk in the D-SLR world by acquiring a Pentax Kx plus the kit lenses 18-55 and 50-200. Later I purchased 3 more lenses of decent value and output quality. I consider now about replacing my original set by a K5 plus kit WR lens, and keep using the other lenses, too (Pentax DA 35/2.4, Tamron 90/2.8 and Tamron 70-300 f4/5.6).

My question is whether this is worth the money needed, because, as per our economic situation in Greece now, the exchange cost is estimated at about 400 euros.

Cheers,

Nick

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