Are you Rice High?
pay attetntion at the best-selling primes from Pentax in Japan
http://kakaku.com/camera/camera-lens/ranking_1050/page=5/
1. DA35/2.4
2. DA70
3. PENTAX-DA 40mm F2.8 Limited
4. PENTAX-D FA 100mm F2.8 WR
5. PENTAX-DA 35mm F2.8 Macro Limited
6. FA31mmF1.8AL Limited black
7. PENTAX-DA★ 300/4
8. FA31mmF1.8AL Limited silver
9. PENTAX-DA 15mmF4ED AL Limited
10. PENTAX-DA★ 55mmF1.4 SDM
11. FA43mmF1.9 Limited
12. PENTAX-DA 50mmF1.8
13. FA50mmF1.4
14. FA77mmF1.8 Limited
I mean that FA Limited, especially, FA31 is very popular lens. Black and Silver. And FA43 too.