Samsung Galaxy Tab S 10.5" Broadband LTE-A

Is the Samsung Galaxy Tab S 10.5" Wif-Fi( Exynos 5 Octa (5420) ) still worth buying at £330/5 or is there something better? I will be coming from the Shield which scores a mighty 29989 on Futuremark, however the 8" screen is not quite big enough otherwise it would be perfect. I read in some reviews the Tab S(FM:13364) can be sluggish at times, although I might install CM if available which could help with performance.

My other question is where can I buy the more powerful versions of this tablet, there is the Exynos 7 Octa (5433) and I believe there is also a snapdragon version. The Exynos 5 Octa (5420) version being sold in the UK has the lowest performance of the bunch.....

Samsung Galaxy Tab S 10.5" Broadband LTE-A
Exynos 7 Octa (5433)
Up to 1.9 GHz quad-core ARM Cortex-A57 and 1.3 GHz quad-core ARM Cortex-A53
Mali-T760
Futuremark score: 19850

Samsung Galaxy Tab S 10.5" Wif-Fi
Exynos 5 Octa (5420)
Up to 1.9 GHz quad-core ARM Cortex-A15 and 1.3 GHz quad-core ARM Cortex-A7
Mali-T628 MP6
Futuremark score: 13364