If you search the net, you ought to find a lot of these comparisons.
I only own Metastock, so I can't tell you much about Tradestation.
MS comes in two versions: EOD and Realtime. The realtime version costs a lot more dollars than the EOD version.
The charting capabilities of MS are excellent, besides the usual type of charts you will also find e.g. Kagi and Three Line Break charts, even if you do not use them, it is interesting to understand the concepts behind these charts. Some people rate the charting capability of Supercharts (not Tradestation) higher than that of MS.
The experts and the scanning features (explorer) in MS are ok. The built-in indicators cover a wide range and the indicator builder allows you to define your own ones.
The weak part of MS is the system tester: if you do not have a system tester just now, it will keep you busy for quite a while, but then you will start to feel its shortcomings. There are no "For.." loops, access to trade variables as entry-price, number- of-bars-in-trade from within a trade are not possible or not straightforward. This can be done with ease in Tradestation.
Also, accessing other securities to evaluate one security (like using relative strength etc.) is difficult and limited in the EOD version but quite easy in the realtime version (via the security command).
I used the realtime features of MS with eSignal as datafeed and did not like it. Other people are highly satisfied, so this my very personal opinion. MS is essentially an EOD program with realtime data crammed into it, quite a difference to a programm that has been designed around realtime data. Note that charting of intraday data and charting of realtime data are different things. But again this is my very subjective view.
As I understood, TS is now longer available for sale, it can only be leased, just like CQG. Look at their homepage for details.
I think you should not limit your choice to MS vs TS, have a look at eSignal with Ensign, Wealth-lab, Trading Recipes, CQG. Other people will certainly suggest other alternatives.
You should decide first what you want: processing of EOD Data, intraday data, scanning and charting realtime data, extensive portfolio testing etc.
Have a look at the software section of
www.traders.com, the homes page of "Technical Analysis of stocks and commodities". They list quite a lot of software vendors, you can search their list with a lot of criteria.
regards
Bernd Kuerbs