The all new 2.71 SE Firmware has compelled ChaosZero to make the 2.71 SEA Firmware Installer. Thanks to him you can easily install Dark_AleX's 2.71 Custom firmware.
Firstly, here are a list of the features:
1.00/1.50 Eboot support (both kernel and user mode).
2.71 Eboot support (both kernel and user mode).
Runs on 2.71 VSH.
Ability to run Devhook (both 1.50 and 2.71 versions are fully compatible).
Ability to run all 2.71 (and lower UMDs).
1.00/1.50 prx executable support.
Support both KXploited and unpatched eboots for 1.50 kernel.
Support any 2.71 homebrew coded for HEN C.
Compatibility is 100% for 2.71 homebrew and approx 99% for 1.00/1.50 homebrew.
Recovery mode.
Note: There are two small bugs. Choosing your language as Korean/Chinese is not allowed. Secondly, running the official updater is not recommended. It will give you an error. In case you want to update/downgrade, you can use Dark_AleX's generic downgrader to downgrade.
Now how is this different from HEN_C, you may ask. Well, like I said, it's all rolled into one cool seamless package. You won't need to run the Homebrew Enabler before running any homebrew. Secondly, it has been confirmed that you will be able to load your firmware mods which you've been using on the 1.5 custom firmware. So looking at the features, I'll probably stick my neck out and proclaim that the days of firmware 1.5 are numbered.
Download here:
here