The three lieutenants have been compared to the Elven Lords, and so it seems reasonable to compare them directly. Superficially, they might seem similar, but let's compare Gorfaur to Elrond, the most commonly used of the Elven lords.
Their prowess, body, and MPs are identical. Gorfaur loses on the discard body check, but that can be eliminated with By the Ringwraith's Word. Elrond costs another mind for another DI, but Gorfaur has an extra DI against Orcs & Trolls. Both allow an extra card to be held when they are at home.
Superficially, then, they might seem very similar. However, this is definitely not the case.
No consideration of Elrond is complete with out Vilya, and this is a huge advantage. It allows Elrond to sit around at Rivendell and recycle cards, while Gorfaur has no such mitigating factor - if he's at Dol Guldur, he's largely wasting his time. Plus, Vilya is multi-purpose - it can make Elrond neigh-invincible on the road.
To balance this out, Gorfaur has access to a number of Leader cards. Most of these allow the leader to benefit the members of his company in some way (prowess, body, corruption bonuses) at the cost of some DI. All can be somewhat useful. The key is, though, that they all require you to actively use your Leader, so the one card hand bonus is largely wasted. Gorfaur also can take trophies, which can increase his prowess and DI a couple of points.
The other advantage that Elrond has is that he can sit around in Rivendell controlled through a Wizard's DI. None of the Ringwraiths have enough direct to control Gorfaur.
So, despite the superficial similarities, the various Lieutenants are lacking some key points that give the Elven Lords their usefulness - the Rings, Cirdan's attack-cancelling ability, and the ability to be controlled through DI (either by a Wizard or, in the case of Galadriel, by Celeborn) to make their high mind more manageable.
Given this, what advantage is their to using Gorfaur, then? Well, firstly he's a sage. As you might expect, sages are kind of hard to come by in Orc and Troll companies. This gives them access to Test of Fire, a very important card since it can solve the corruption problems associated with untested rings, and it allows these companies to actually use the resultant ring rather than having to test by storing. It's hard to understate the importance of this capability.
Secondly, he has has a whopping 5 DI against Orcs and Trolls. This would allow him to control up to 3 decent-prowess followers. Add a Whip, and his DI jumps to 7, allowing him to control a small army. This mitigates somewhat the huge amount of GI invested in him. Add a Blazon of the Eye, and Orc and Troll factions (as well as many other factions!) will follow his lead.
Thirdly, unlike Elrond, there is no penalty for his loss. The minions of the Dark Lord are *all* expendable. This means you can use him aggressively without much worry.
As always, the GI investment is the catch. 9 GI is such a large chunk of your starting allotment, it makes it hard to field anyone else - and it almost certainly restricts you to one overt company only. Given the difficulties involved in using Orcs and Trolls, and their tendency to incur more casualties than your overt companies, you need to be careful. You could still free up a lot of GI on turn one, though, by taking advantage of his potentially large DI.
In the end, though, I believe the one-card hand bonus is there to tempt you. Any reasonable strategy involving the Lieutenants is going to involve utilizing their propensity for bashing stuff (and leading others who bash stuff). Leaving them sitting around in the various Darkhavens wastes their talent, and doesn't have any additional mitigating factors like it does in the case of Elrond and Galadriel (Vilya and Nenya).
IMHO, the Lieutenant of Dol Guldur is the best of the Lieutenants. His sage skill and extra DI more than make up for the one-point loss in prowess. I am still not sold on the real value of Rogrog and Gothmog, but Gorfaur is definitely a very useful character when your deck is tuned to take advantage of him.
Original card review taken from : http://fan.theonering.net/morgulrats/
With the authorization of the webmaster.
The reviewing team consisted of Gwaihir (Chris Farrell), Gimli (Nathan Bruinooge), Ohtar (Charles E. Bouldin, Esq.), Radagast (James Kight), Joshua B. Grace (Beorn), Martijn Steultjens (Fram Frumgarson), Jason Klank (Saruman) and Jeffery Dobberpuhl (Wormtongue)