It seems to me that quite some vipassana masters are kind of against samatha practice
Samadhi produces very blissful feelings and most teachers warn against getting stuck on these states:
From Ajahn Chah:
On Dangers of Samadhi
Samadhi is capable of bringing much harm or much benefit to the meditator, you can't say it brings only one or the other. For one who has no wisdom it is harmful, but for one who has wisdom it can bring real benefit, it can lead him to Insight.
That which can be most harmful to the meditator is Absorption Samadhi (JHANA), the samadhi with deep, sustained calm. This samadhi brings great peace. Where there is peace, there is happiness. When there is happiness, attachment and clinging to that happiness arise. The meditator doesn't want to contemplate anything else, he just wants to indulge in that pleasant feeling. When we have been practicing for a long time we may become adept at entering this samadhi very quickly. As soon as we start to note our meditation object, the mind enters calm, and we don't want to come out to investigate anything. We just get stuck on that happiness. This is a danger to one who is practicing meditation.
We must use Upacara Samadhi. Here, we enter calm and then, when the mind is sufficiently calm, we come out and look at outer activity. Looking at the outside with a calm mind gives rise to wisdom. This is hard to understand, because it's almost like ordinary thinking and imagining. When thinking is there, we may think the mind isn't peaceful, but actually that thinking is taking place within the calm. There is contemplation but it doesn't disturb the calm. We may bring thinking up in order to contemplate it.
Here we take up the thinking to investigate it, it's not that we are aimlessly thinking to investigate it, it's not that we are aimlessly thinking or guessing away; it's something that arises from a peaceful mind. This is called "awareness within calm and calm within awareness." If it's simply ordinary thinking and imagining, the mind won't be peaceful, it will be disturbed. But I am not talking about ordinary thinking, this is a feeling that arises from the peaceful mind. It's called "contemplation." Wisdom is born right here.
So, there can be right samadhi and wrong samadhi.
Wrong samadhi is where the mind enters calm and there's no awareness at all. One could sit for two hours or even all day but the mind doesn't know where it's been or what's happened. It doesn't know anything. There is calm, but that's all. It's like a well-sharpened knife which we don't bother to put to any use. This is a deluded type of calm, because there is not much self-awareness. The meditator may think he has reached the ultimate already, so he doesn't bother to look for anything else. Samadhi can be an enemy at this level. Wisdom cannot arise because there is no awareness of right and wrong.
With right samadhi, no matter what level of calm is reached, there is awareness. There is full mindfulness and clear comprehension. This is the samadhi which can give rise to wisdom, one cannot get lost in it. Practitioners should understand this well. You can't do without this awareness, it must be present from beginning to end. This kind of samadhi has no danger.
You may wonder where does the benefit arise, how does the wisdom arise, from samadhi? When right samadhi has been developed, wisdom has the chance to arise at all times.
When the eye sees form, the ear hears sound, the nose smells odor, the tongue experiences taste, the body experiences touch or the mind experiences mental impressions in all postures -- the mind stays with full knowledge of the true nature of those sense impressions, it doesn't "pick and choose." In any posture we are fully aware of the birth of happiness and unhappiness. We let go of both of these things, we don't cling. This is called Right Practice, which is present in all postures. These words "all postures" do not refer only to bodily postures, they refer to the mind, which has mindfulness and clear comprehension of the truth at all times. When samadhi has been rightly developed, wisdom arises like this. This is called "insight," knowledge of the truth.
There are two kinds of peace - the coarse and the refined. The peace which comes from samadhi is the coarse type. When the mind is peaceful there is happiness. The mind then takes this happiness to be peace. But happiness and unhappiness are becoming and birth. There is no escape from samsara 2 here because we still cling to them. So happiness is not peace, peace is not happiness.
The other type of peace is that which comes from wisdom. Here we don't confuse peace with happiness; we know the mind which contemplates and knows happiness and unhappiness as peace. The peace which arises from wisdom is not happiness, but is that which sees the truth of both happiness and unhappiness. Clinging to those states does not arise, the mind rises above them. This is the true goal of all Buddhist practice.