I use TKL and HHKB. I can touch type numbers in the top row. However, for a lot of number entry, there is no question that a tenkey is more efficient. So...I have a numberpad. I have the Realforce numberpad, but here's a nice Filco with browns for $45:
http://www.amazon.com/Filco-Majestouch-TenKeyPad-Tactile-Numberpad/dp/B000MGBPNI/ref=sr_1_1?ie=UTF8&qid=1390773579&sr=8-1&keywords=filco+numpadMy numpad sits under my display. I simply pull it out when I need to do a lot of number entry. My accountant comes to my office once a week to do my accounting. Nobody does more number entry than an accountant, and this guy tenkeys so fast, you almost can't differentiate individual keystrokes. He liked my separate numpad so much that he ordered a Filco TKL and the above numpad and dumped his full sized Das board. That was six weeks ago. I asked him last week how he likes the new setup. He said he'll never go back to a full sized board with attached numpad.
Regarding compact layouts: I'm a programmer, and I've been using my HHKB about 75% of the time these days. Once I adjusted to using the secondary layer, it's actually faster than a standard keyboard layout simply because of reduced finger movement. F keys can be actuated without reaching. I run three displays, so easily moving windows between them is a must. I can do that on the HHKB with my right hand. That requires two hands on a standard layout. Keyboard shortcuts are faster too.
One of the best changes I made on my HHKB was making the left Win key a Fn key. Now I can use arrow keys, PgUp, PgDn, Home and End without leaving home row...and without taking my eyes off my display. Seriously, it's really fast to navigate.
Compact doesn't come without some cost however. I miss having a right Control key. I'd like to have a left Win key in addition to the Fn key. However, these are minor issues when compared to the benefits of a compact layout.
Another benefit is mouse use. I know this doesn't concern most users, but I mouse with both hands and have a mouse and mouse pad on each side of my keyboard. I'm right handed, but left mouse about 60% of the time. When I game, I use left mouse. Having a compact or TKL board allows me to keep my mice in close on each side.