OP, don't know if there's any discussion of the issue in Liam's links but one issue you need to consider is your marginal tax rate.
The simple fact is that a higher rate payer receives more than double the amount of tax relief per contribution than a lower rate payer.
The tax relief is what makes pension savings efficient.
If you're a lower rate payer now but expect to move into the tax bracket in the vaguely foreseeable future, then you'd probably be well advised to hold off starting a pension plan.
In any event, your moniker implies you want to get house purchase sorted as something of a priority. If I were you I'd consider saving for that before rushing into a pension. Let's face it, you're not exactly missing out on a bull market in either equities or property at the moment.